Singapore: Medical Device Regulatory Syste
Jack Wong, Raymond K. Y. Tong in Handbook of Medical Device Regulatory Affairs in Asia, 2018
In vitro diagnostic medical device is any reagent, reagent product, calibrator, control material, kit, instrument, apparatus, equipment or system, whether used alone or in combination that is intended by its product owner to be used in vitro for the examination of any specimen, including any blood or tissue donation, derived from the human body, solely or principally for the purpose of providing information:Concerning a physiological or pathological state or a congenital abnormality;To determine the safety and compatibility of any blood or tissue donation with a potential recipient; orTo monitor therapeutic measures
Experimental Models of Status Epilepticus
Steven L. Peterson, Timothy E. Albertson in Neuropharmacology Methods in Epilepsy Research, 2019
The primary requirement of an experimental model of SE to be used in the testing of new anticonvulsants is that it exhibit the same sequential electroenceph-alographic changes that have been shown to occur in human SE. This requirement is met by HCTL, kainic acid, both pilocarpine models, SSLSE, and the in vitro models. Kainic acid has the complications of variability in response, direct excito-toxicity, and it is not responsive to anticonvulsants currently effective in human SE. Pilocarpine-induced SE has the complications of high mortality and also does not respond to anticonvulsants effective in human SE. The in vitro models are relatively new and need further characterization. This leaves HCTL and SSLSE, which are both labor intensive but only HCTL is responsive to anticonvulsants effective in human SE.
Eukaryotic Dna-Dependent Rna Polymerases: An Evaluation of Their Role in the Regulation of Gene Expression
Gerald M. Kolodny in Eukaryotic Gene Regulation, 2018
Current evidence suggests that the Late Adenovirus-2 genes are transcribed as a gigantic polycistronic message (approx. 30,000 bases).198 The maturation of individual late mRNAs requires the splicing of 3 short sequences from the 5-end to a protein coding sequence from within the primary gene transcript.14 Ziff and Evans199 identified and sequenced the late transcription initiation point at 16.45 map units in the Adenovirus-2 genome. Using a restriction enzyme fragment containing this presumptive promoter and purified RNA polymerase II, Weil et al.197 were able to reconstitute an in vitro transcription system which initiated RNA synthesis accurately. They corroborated what others had recently found that the purified RNA polymerase lacked certain initiation “determinants” (see Reference 197). In this case, accurate initiation was only achieved when the transcription system was supplemented with a crude cellular extract (‘S-100’).
Success of in vitro fertilization and its association with the levels of psychophysiological stress before and during the treatment
Published in Health Care for Women International, 2021
Nathália Karen Maia Bezerra, Ana Cecília de Menezes Galvão, Nathalia Evelyn Martins Leite, Adriana Leão Barbalho Sant’anna, Mychelle de Medeiros Garcia Torres, Maria Cecília Galvão Pinto Coelho, Victor Kenji Medeiros Shiramizu, Maria Bernardete Cordeiro de Sousa, Nicole Leite Galvão-Coelho
In vitro fertilization (IVF) is a technique in which fertilization is performed in the laboratory, where viable embryos are transferred to the woman’s uterus, and it has been the preferred alternative of treatment for women who have difficulty to conceive naturally (Dzik et al., 2012). It is estimated that about 600,000 IVF are performed worldwide each year, with Europe accounting for approximately half of the global treatments (Zegers-Hochschild et al., 2017). High rates of IVF are also observed in Brazil, with approximately 27,269 treatments per year (Zegers-Hochschild et al., 2017). Despite the increasing demand and advances in the field of assisted reproduction, treatment success rates of IVF (considered as those using fresh embryos) are around 30%–35% (Andersen et al., 2008; Cesta et al., 2018; Silva et al., 2014). Thus, raising pregnancy rates is the main challenge in this area.
Live birth rate following undisturbed embryo culture at low oxygen in a time-lapse incubator compared to a high-quality benchtop incubator
Published in Human Fertility, 2022
Dimitrios Kalleas, Keith McEvoy, Gregory Horne, Stephen A. Roberts, Daniel R. Brison
In vitro fertilization (IVF) is a well-established method of infertility treatment and more than 8 million IVF-conceived children have been born worldwide (European Society of Human Reproduction & Embryology, 2018). However, success rates remain relatively low and the IVF laboratory environment is not yet fully optimized. In particular, a major barrier to progress in the field has been the need for multiple observations of embryo development, in order to assess/monitor normal growth and facilitate selection of the best embryo for transfer based on morphological criteria (Alpha Scientists in Reproductive Medicine & ESHRE Special Interest Group of Embryology, 2011). Conventionally, this has involved removing embryos repeatedly from stable incubator conditions to a benchtop microscope in the open laboratory, incurring exposure to light, potential volatile organic compounds, as well as changes in temperature and gas concentration, which affect the pH and osmolality of culture media.
Pituitary adenoma and apoplexy during GnRH agonist treatment for IVF - case report
Published in Gynecological Endocrinology, 2020
Aneta Stefaniak, Jan Domitrz, Katarzyna Siewko, Małgorzata Szelachowska, Adam Krętowski, Alicja Stachura-Matyjewicz
In vitro fertilization (IVF) is commonly used for treating infertility. One stage of this process is controlled hyperstimulation of the ovaries, achieved by administering gonadotropins. There are several stimulation protocols utilized that increase the number of ovarian follicles during IVF. The most common protocol employs desensitization - the inhibition of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) secretion by the pituitary gland. This is achieved by administering a GnRH analog that is agonistic for the GnRH receptor. The drug is most commonly administered from the halfway point of the luteal phase of the preceding cycle. Administration of 50–100 µg of GnRH agonist directly inhibits gonadoliberin secretion and indirectly inhibits FSH, LH, and estradiol after around 10–14 days. However the use of a this drug during therapy carries a risk of complications. The most common complication of using a GnRH agonist with gonadotropins is ovarian hyperstimulation syndrome (OHSS). Rarer complications include ovarian cysts, reduced bone density, and mood changes with depressive characteristics. Extremely rare complications encompass such issues as pulmonary artery embolism, myocardial infarction, and pituitary apoplexy caused by a previously clinically inactive pituitary tumor called gonadotropinoma.
Related Knowledge Centers
- Biomolecule
- In Vivo
- Multicellular Organism
- Petri Dish
- Cell
- Test Tube
- Microplate
- Growth Medium
- Solution
- Omics